Universal indicator clamp



March 13, 1945. w, LARSON 2,371,451

UNIVERSAL INDICATOR CLAMP Filed 001:. 4, 1344 Ju /um wAzee-u H Lazson Patented Mar. 13, .1945

' UNITED STATE-S PATENT OFFICE 2,371,451 v UNIvERsAnINmoAToR CLAMP. W Y Warren flal arson, Minneapolis, Minn.

Application October 4, 1944, Serial-No. 557,207 I 2 Claims. (01. 248-226) This invention relates to improvements in clamps for holding the dial testindicators used in precision machining and tool making in niachine shops.

The ordinary clamp for this purposecomprises a clamp having a single tapped opening in its head to receive the threaded end of a bar or post upon which the conventional dial indicator is clamped orsupported, said postextending coaxially with respect to the clamp spindle or screw. The use of a clamp of this kind is limited, however, to situations wherein it may be secured to some adjacentpart of the machine with itssingle postextended into proximity to I the work to properly support the indicator with respect thereto, and in many instances it will be found either that space does not permitthe proper-positioning of the clamp, or that when the clamp is located in a suitable place the post cannot be disposed adjacent the work at all. Then too, and this is important, in much work several tests must be applied to the work and these must now be carried out in succession or one at a time with the single post type of clamp, greatly increasing the total time for testing and setting upthe work.

Having in mind these facts it is the primary object of my invention to provide a universal clamp for this purpose whereon a plurality of indicator supporting posts may be arranged at spaced and angularly related positions with respect to each ,other and set up in any combinations suitable to the work. Thus the clamp itself may be secured to the machine, or any supporting part convenient to the purpose, and a post attached to the clamp at an angle and position such as, in the majority of cases, to bring the indicator mounted thereon to operative position with respect to the work. A further object is to pro vide a multiple post clamp whereon two, or even more, posts may be arranged to support any number of separate indicators required for simultaneously testing and indicating the trueness of different surfaces of the work. Thus the work may be trued up in one operation, so to speak, with a. considerable reduction in the setting up time for each piece.

These and'other more detailed and specific objects will be disclosed in the course of. the following specification, reference being had to the accompanying drawing, in which- Fig. 1 is a fragmentary plan view of a lathe and a work piece mounted therein and illustrating the simultaneous checking of the end and peripheral surfaces of the work by two separate dial indicators clamp,

Fig. 2 is an enlarged side elevation of the clamp and two posts associated therewith.

Fig. 3 is a plan or head view of the clamp alone. Fig. .4 is a fragmentary sectional view along the lined-4 in Fig. 2.

supported by two posts in my universal 1 Referring now more particularly .andnby reference charactersto the drawing my improved clampis indicated generally at 5 and comprises a substantially G-shaped frame 6 having an upper arm, I, andvlower arm .8 connected by a back member. :9, all suitably ribbed for strength as clearly shown. Formed at the end of the upper arm I is a head Hi andat'the corresponding end of the lower arm .8 is an integral tapped sleeve 1 I: through which is threaded a spinjdle or clamp underside of the head In with a shallow v-shaped notch l5 for convenience in rigidly and properly gripping the support, whatever it may be.

In the ordinary clamp as supplied the tool maker or machinist for this purpose at present, the head In is provided with a single tapped socket or opening in the location here designated at It, to receive the threaded, reduced end I! of an indicator mounting post or bar l8 which, when screwed with said socket, obviously extends straight from the clamp in substantially axial alignment with the spindle I2.

In accordance with my invention I provide any number of additional posts l8, as indicated in the drawing, and for their selective reception provide the clamp head l0, in addition to the one socket H5 in its upper side, with three similar tapped sockets I9, 20 and 2| disposed each substantially at right angles to the other and located respectively in the front 22, and sides 2324 of the head which as clearly shown is square in shape to provide the necessary surfaces for this purpose. 7 Toprovide a base, or shoulder against which the posts may be tightly screwed the outer ends of the sockets l8, l9,20 and 2| open through surrounding, faced-0H generally circular bosses indicated at 25.

Referring now more specifically to Fig. 1, I

illustrate therein a. situation in which my im-' proved clamp is of great advantage. Here the must be run true in a plane at right angles with that axis.

In the previous practice it wo ld be necessary to first check either surface D or: E or the-work by first adjusting the clamp and indicator thereto, and after trueing that surface, to shift the clamp and indicator to another position suitable for checking the last surface. only require a considerable time and duplication of efforts but might easily result in repe'atedtests factors.

two posts and indicators, and any number may be employed, and the posts disposed in any of the sockets in the clamp as may be required for each individual job. In addition the wide choice of angles of a single post with respect to the clamp, makes it possible to meet the requirements in many set-ups where the single post, extended straight from the clamp as hereinbefore set forth, wouldnot be useful atall due 110,. crowded conditions; intervening obstructions between the work andonly available clamp position, and other Further advantages of my clamp will be readily appreciated to those skilled in the This would not l being required after each adjustmentf'ofthe'workin the chuck, as will be readily apparent.

In the use of my improved clamp, however, I ma as: indicated; secure it to the latheat any appropriate point and in the instance illustrated alibi two' separate posts;designated at 1-8, and 18 at right aldgleS-toeach other and extendin respectively toward the peripheral; and end surfaceD and E of the work A- In the particular mounting shown the posts we and 18 are, respectively screwed into the sockets 20. and 15 in the head in or the'clamp; By means or the conventional fixtures and clamps F provided for this purpose rthen may: support separate: dial test indicators Gland-G2 on the posts! and .18 so that their work contacting'points properly ride the surfaces D and E of the work as shownto simultaneously indicate any deviations on these surfaces from true, and indicate the eflectiveness 'ofth'e connections as they are made. Thu's'I secure a great; saving of-tim'e in setting up each pieceas'vviltbe clearly evident} 'My clamp is not, of course, limited to use of art without further description herein.

It is understood that suitable modifications may bemade in'the structures disclosed, provided that such modifications lie within the spirit and scope of the appended claims. Having now, therefore, fully disclosed my invention, what I claim to be new and-desire: to secure: by: L tters, Bat t is:

L A; device, of he" har c er c e o 'ibeeli u por n a p u tr Q d a test indicators in positions for simultaneously taking readings irom separatesurfaces of the work bein tested and including: posts iorv carrying the-indicators, com rising a clamp member i cl i g ahead havin a plurality. of: angularly positioned-sockets dapted to selectively receive and support the posts in-position f0r properly presenting the indicators thereon to-the work, the said sockets beingalldisp ed a right an les to each other.

. 2. A clamp for selectively supporting one or more dial indicatormounting; posts, comprising a clamp framehaving a squareheadporticnam said head portionhaving post receiving sockets opening through at leastiour surfaces at ri ht angles toeach other.

H. LARSON. 

